Safety-fuse.



S. J. LBVBBN 6v E. A. MARTIN.

I SAFETY FUSE.

APPLIUATION rILEn mxo. 4, 1907.

Patented Nov. 8, 1910.

2 SHEETS-SHEET 1.

S. J. LEVEBN `& E. A. MARTIN.

SAFETY FUSE.

PPLIOATION FILED 1120.4, 1907.

fag.

@wi/immo@ @1% UNITED STATES PATENT FFICE.

SWAN J. l.LEVIEJJJW ANI) EDWARD A. MARTIN, OF ROCKv ISLAND, ILLINOIS, ASSIGNORS, BY .MESNE ASSIGNMENTS, TO TRIO MANUFACIU'RING COMPANY, .A CORPQRATION OF ILLINOIS.

SAFETY-FUSE.

.Application filed December 4, 1907.

To all whom it may concern:

Be it lmown that we, SWAN J. Lnvnnn and EDWARD A. MARTIN, citizens of the United States, residing at Rock Island, county of Rock Island, State of Illinois, have made a certain new and useful Invention in Safety# Fuses, of which the following is a specication.

The invention relates to safety fuses, and particularly to the 'type of fuses known as inclosed safety fuses.

The object of the invention is to provide a safety fuse of simple construction, economical to manufacture, and which is eiiicient in use.

.A further object is to provide a safety fuse, of the character referred to, having few ainperage or other desired rating of the fuse. i

Other objects of the invention will appear more fully hereinafter.

Theinvention consists substantially in the construction, combination, location, and rel ative arrangement of parts, all as will be more fully hereinafter set forth, as shown in the accompanying drawings and finally pointed out in the appended claims.

Referring to the accompanying drawings and to the various views and reference signs appearing thereon, Figure 1 is aview in side elevation of one form of safety fuse embodyin our invention, all the v arts being assembIed and the device rea'y for use.

y Fig. 2 is a view in longitudinal section of the same. Fig. 3 is a broken View in longit-udinal section, ofthe end of the casing, showing means for securing the fuse strip therein. Figni is a similar view of the end cap or' ferrule, showing the mannerk of mounting the terminal contact plates. Fig. 5 is a detached view of the fuse strip. Fig. 6 is a viewsimilar to Fig. 1, showing a modified fornizbf fuse embodying the prin ciplcs of our 'invention'. .Fi-gli is a view inl longitudinal section ofthe construction shown in Fig. 6. Fig. 8 isffa'-broken view in Specification of Letters Patent.

- shown .in the drawings.

lvaigle or desirable manner. asimple arrangement wherein the caps are Patented Nev. e, 1910.

Serial No. 405,06.

longitudinal section of the end of the fuse case shown .in Fig. 6. Fig. 9 is a similar view of the end cap or ferrule employed in connection with the forni of fuse shown in Fig. 6 and showing the manner of mounting the terminal contact plates. Fig. 10 is la view similar to Fig. 5, showing a slightly modified form of fuse strip. Figs.l 1l and 12 are views in longitudinal section of the fuses respectively shown in Figs. l and 6, the plane of section being at right angles rto the plane of section of Figs.. 2 and 7.

The saine part is designated by lthe same v reference sign wherever it occurs throughout the several views.

In the construction of fuses, and particularly fuses of the inclosed type it is desirable that the various parts thereof be simple in construction, and capable of being readily and easily assembled, and that the fusing part, when blown, may be readily and easily replaced, that means be provided which are reliable and positive in operation for readily revealing on inspection whether or not the fuse has been blown, and that means be rovided to enable the rating or capacity o the fuse to be revealed on inspection.

It is among the specialv urposes of our present invention to provi e a fuser which embodies .these various desirable features.

In carrying out our invention we employ a casing A of suitable insulating, and

preferably llire proof material, adapted to receive and contain the fuse strip II, therein. This fuse ,strip muv be of any suitable or convenient material, such, for instance asI zinc, adapted to fuse or burn out under the current conditions to which it is designed. In practice we prefer to employ a flat strip, as shownhavin'g a portion intermediate its ends, of reduced width, as indicated at M. This fuse strip is inserted and inclosed longitudinally 'within the case, and is surrounded with a suitable powder or other composition K, in the usual manner, the function of which is to absorb the gas and smother the arc when the fuse blows. Caps I, are secured in the ends of the case and serve to close such ends, said ca s having slits or openings therethrough t rough which the ends of the fuse strip extend, as clearly The caps I may be secured in the ends of the casein any suit- We have shown provided with annular' flanges R, which bear against the end surfaces of the casing, and we provide the fuse strip H with tongues J, stamped out of the body thereof and which are arranged to engage against the outer face of the caps, as clearly shown, thereby not only holdingthe caps in place, but also securing the fuse strip in place. These tongues J, may be formed midway the transverse width of the fuse strip, as shown in Fig. 5 or they may be formed in the edges thereof as indicated in Fig. lO. It will be readily seen that the tongue at one end of the strip engages and bears against the outer surface of the cap at that end of the case while the tongue at the other end of the strip engages and bears against the outer surface of the cap at the other end of the case, that is, the surface which presents in a direction opposite to that in which the outer surface of the other cap presents, and consequently the caps and also the strip, are thus easily assembled and etliciently secured to the case.

The ends of the fuse strip extend beyond the caps I, and these extending ends form the circuit terminals of the fuse. In order to form efficient bearing contact for these projecting ends with the line terminals, we arrange said ends to be received between contact blades'or plates. These may be ar ranged for use in connection with knife clip line terminals, asI indicated at D, Figs. l, 2, t and il, or in the ferrule type of fuses, as indicated at D', in Figs. 7 and 9.

The blades or plates D, D, are shown of angle form, but our invention is not lto be limited or restricted in this respect. In the case of the knifeclip type the angle portions of these blades or plates are secured by meansY of rivets G, or other suitable devices on the inner surface of cups or ferrules C, which are designed to slip over or upon the ends of the cases and which may be held thereon by friction or otherwise, and'which not only serve to carry the contact blades or plates but also to give a finished appearance to the fuse. The ends of the contact blades or plates extend through a slot or opening in the cup or ferrule, and outside of the case, and the projecting ends of the fuse strip are received therebetween as clearly shown. lf desired, and in order to enable the contact blades or plates to readily adjust themselves to their bearing Contact against the end of the fuse strip, the securing rivets G, may be arranged to pass through elongated slots L, in the ferrules, as shown in Fig. 4. thereby permitting slight movement of the blades orA plates in adjusting themselves to etlicient contact with the ends of the strip.

ln the case o'tl the fel-rule type instead ot the contact' blades` or plates D. extending through the cups or l'errules (.l. said plates the outside of the case A, but in this respect we do not desire to be limited. This wire is formed into a loop at l, into which is engaged the hooked end of a spring indicator E. This indicator is suitably secured at one end as, for instance, to the case and when the hooked end thereof is not engaged in the loop l), said spring stands out away from the case, but when the hooked end thereof engages in the loop 'said spring is held down againstI the side of the case. It will be seen that this arrangement provides a most etlieient, simple and positive indicator for revealing on inspection whether or not the fuse has been blown.

The rating or capacity of the fuse may be revealed in man v different ways. in Figs. l and t3, we have shown labels l. adapted to be applied to the case and on which the information regarding the rating or current capacity of the. fuse, as well as other intormation or directions may be printed. This label may be applied over the indicator wire thereby affording means for protecting such wire. ln this case. the label is provided with :rhole through which the loop P. of the wire extends.

If desired the rating and current capacity of the fuse may be indicated in other ways. lVe have shown a simple, and etiicient way for accomplishing this result wherein we extend the ends of the fuse strip beyond the ends oi the plates orblades D, see Figs. l. 2 and 4. In this case tht` strip may have stamped or otherwise placed on such projecting end the desired information as to its rating or current capacity.

From the foregoing description it. will he seen that we provide an exceedingly simple and etiicicnt fuse. which can be economicalljf manufactured, and readily and easily assembled, and ot such structure that when il is blown the most expensive parts, namely. the ferrules and contact plates are saved thereby enabling the fusible part to be readily renewed. lt will also be seen that on inspection it may be revealed at once whether or not the fuse is blown` and also the rating or currentcapacity of the fuse.

Having now set forth the object and nature of' our invention and various coustructions embodying the principles thereof, what we yclaim as new and useful and our V own invention and desire to secure by Letenh l ters Patent iszarranged therein engaging means between thecase'and fuse elementfor locking these )arts together, having its ends extending eyond the case,a cup removably mounted on eaclrend ofthe case, and voutwardly extending contact plates' carried by said cups to receive therebetween'the projecting ends of the fuse element, said Contact plates being independently and loosely mounted for relative movement whereby they adjust themselves to the fuse element'ends.. v Y

3. 'In a safety fuse, a case, a fuse element arranged therein and having its ends extendin beyond the ends -of the case, cups for'the en s of the ease, and self adjusting contact'- plates independently mounted on' said eu 5,: and' arranged to receive therebetween t e. projecting ends of the fuse strip. L1.In a fuse, a ease,l a fusible strip arranged therein engaging means between the fcase and fuse strip for locking these'parts together, said fuse strip Ahaving its ends ex- Atended beyondthe ends ofthe ease andremovable cups for-the 'ends of the case, said cups carrying outwardly extending looselyA mounted contact plates to receivethe extending ends of the fusible str i therebetween,

' and means for clamping sai plates together `w,hereby said'contact plates are self adjusting to bearing contact against said ends.

In a fuse,va` case, a continuous strip Q extending through the cas and indepen ently land loosely mounted ontaet plates arranged at the ends of the case to receive the ends of the strip therebetween.

(i. In a fuse, a case, a continuous. fuse strip extending through saidcase, means for 'locking the same therein, and independently and looselymounted contact plates, arranged in pairs and carried by the ends of the case. to receive therebetween the ends of said strip.

7. In a fuse, a ease, a continuons fuse strip extending through said case andself adjust` ing contact plates to receive the ends of said 8. In a fuse, a case having caps at the endsl thereof and a fuse strip extending to hold the tstogethe. 1 13. In" a use, af'ase?having"closedends,y ya fuse strip extendingthrough saidr case and havingthe'ends thereof projectingbe ondA ands@ .fia just-:-

4ingcontact means to engage the' projecting through theca-se and *beyond the caps 'and' engaglng -the caps on the outer end surfaces thereof, and in opposite 'directions whereby the parts are held together.i

9. In a fuse, a case having'caps lat the ends thereof, and a fuse `stri Aextendn through the case andl beyond t e caps an having tongues toengage againstthe outer 70 surfaces of the caps.

10. Inajuse, a case having caps inthe ends thereof, a fuse'stri extendingthrough the case and caps, an .self-ad'ustin'g-con-Q tact plates to engage the exten ing' ends of the strip.

' 11'. In a fus-e, ay case'havingr caps in they ends thereof, a fuse-stri extending through the case and caps, and aving Vmeans to engage the caps to loekutheparts rigidly together, and contact means tolengage the endsv of the strip.

` 12.; Ina fuse, a havingA flanged caps 'y i `in the ends thereof, the v`flanges of the, caps 'Y bearing against the-Lend surfaces of the case. v

and a fuse vstri jextendinglg` through the ease: 185

and caps and avingmeansto engage the f outer surfaces offthe''eapsfat 'the respective the closed ends of thefcase,

ends of the strip.

vends ofthe case,.and ingo'ppostte,directien sQ 14.-. In a fuse,1a ease havingelosederids, a f

'ruse-snapY extending' through'saidmse; 'andk 'Y projecting beyondA the closed ,ends thereof,

.cu s carried bytheatits endsand proy vi ed with relatively movable clamping oontact plates independently` 'mounted and adapted to receive therebetweenand contactY with the projecting ends of the-strip.

15. -In afuse, a case having closed ends, a fuse strip extending through said case and the closed ends thereof, said fuse strip hav- 'ing a portion intermediate its ends'of reduced Width, and independently and loosely mounted self adjusting contact y'plates ar-v ranged at the closed ends of the case to receive therebetween the'extending ends of the fuse strip.

In testimony whereof we have hereunto set our hands inV the presence of the subscribing witnesses, on thisv26th day of November A. D., 1907.

' SWAN .rnnvnnn EDWARD A. MARTIN.

iVitnesses:

P. B. ZIMMER, C. A. WALKER. 

